Demountable closure



United States Patent l DEMOUNTABLE CLOSURE Leland D. Cobb, Forestville,Conn., assignor to General Motors Corporation, Detroit, Mich., acorporation of Delaware Application December 31, 1952, Serial No.329,019

Claims. (Cl. 2865) This invention relates to a demountable closure forclosing the end space between a pair of relatively rotatable members andparticularly to a demountable seal for retaining lubricant in anantifriction bearing and for preventing the entrance of dirt and otherobjectionable material into the bearing.

It has been the practice for many years to permanently close the ends ofthe annular lubricant chamber between the race rings of an antifrictionbearing by locating across each end of the lubricant chamber aringshaped metal shield or seal and by expanding a foldedover peripheralrim on each shield into permanently wedged engagement with the walls ofa groove in one of these race rings. This rim expansion frequentlydistorts the race ring causing an improper fit of the bearing in itsmounting and also causing an improper fit of the bearing parts whichwere previously ground to within tolerances of a small fraction of athousandth of an inch, all of which often results in much shortenedbearing life. With present day high speed machinery, antifrictionbearings are often subjected to unintended overloads and high operatingtemperatures which reduce lubricant life in the bearings andnecessitates occasional cleaning of the bearings and replacement oflubricant to avoid bearing failure. These permanently installed sealsare. difficult to remove, and even when such seals are broken loose andremoved, the seals are not only ruined but the bearings :are frequentlydamaged to the extent that they have to be replaced. Installation of anew shield usually must be made at the factory where the bearing wasmanufactured. Consequently, it has been regular practice to operate:antifriction bearings without attention and until failure which hasoften been premature due to insuflicient lubrication, resulting in lossof much production time during bearing replacement.

An object of this invention is to provide an improved closure for theend of a lubricant chamber between relatively rotatable members andwhich may be easily mounted in and demounted from position withoutinjury to the closure or to the members with which it is associated. Afurther object is to provide for the end of a bearing an improveddemountable closure of simple and inexpensive construction and having adetachable reinforcing portion.

To these ends and also to improve generally upon devices of thischaracter, this invention consists in the various matters hereinafterdescribed and claimed. In its broader aspects, the invention is notnecessarily limited to the specific structures selected for illustrativepurposes in the accompanying drawings wherein:

Figure 1 is a cross sectional view of a portion of an antifrictionbearing showing two related forms of demountable closures;

Figure 2 is a fragmentary enlarged cross sectional Patented Sept. 25,19.56

exploded view showing my sealing washer and its reinforcing ring; and

Figure 3 is an end view showing a bearing with my demountable sealinstalled.

The closure, as 10, may be frequently and repeatedly mounted anddemounted without injury to itself or to the members with which it isassociated, this closure being shown in demountable closing relationacross the end of an annular lubricant chamber 12 between a pair ofrelatively rotatable inner and outer antifriction bearing race rings 14and 16 provided with the usual raceways that cooperatively receiverolling elements, as balls 18 guided by a separator 20. At each end ofone of the race rings, as the outer race ring 16, there is provided anannular groove 22 transversely curved between a substantially radiallydisposed annular shoulder 24 and a transversely rounded annular land 26which has a diameter intermediate between that of the bottom of thisgroove and that of an inner cylindrical wall 27 of this race ring. Oneend of one of the race rings, as the inner race ring 14, has atransversely curved annular notch 28 and the other end of this race ringhas an annular notch formed by a peripheral wall 30, herein showncylindrical, and a generally radial annular shoulder 31.

In the seal at the right hand end of Figure 1 and in Figure 2, aninherently resilient sealing washer 34 has a peripherally extendingdeformable head 36 and a resilient annular sealing lip 38 connected by alaterally outwardly offset resilient intermediate wall 40 which hasgenerally conical annular portions 42 and 43 that respectively mergewith the bead 36 and with the resilient lip 38. The wall 40, which isnarrow in comparison to the width of the bead 36, is laterally oifset toprovide ample clearance relation with the separator 20 and to providefor additional lubricant space in the chamber 12. As best illustrated inFigure 1, the central bore through the sealing washer 34 is generallyconical and slightly larger in diameter than that of the bottom of thesealing notch 28 so that the inner portion of the sealing lip 38 isresiliently deformed into lightly wiping sealing contact with the curvedside wall of the notch. With this sealing engagement, the lip 38 willnot bottom in the notch 28 and an effective seal is maintained even inthe event of misalignment of race rings.

The resiliently deformable bead 36 has generally flat faced inner andouter annular walls 45 and 46 and a transversely convexed peripheralbead portion 47 merges with the inner wall 45 and with a frusto-conicalannular portion 48 terminating at the wall 46. The width of this bead 36exceeds the width of the groove 22 and the diameter of this yieldablebead slightly exceeds that of the groove 22 thereby providing a beadwhich may be deformably snapped past the annular land 26 into and out ofresiliently tight interfitting sealingly seated engagement against theshoulder 24 and against the groove walls, thus serving to locate theclosure 10 axially and radially in a predetermined position. The conicalannular portion 48 deformably engages the rounded land 26 and extendsoutward beyond the groove 22 to a position where a screw driver or othersuitable tool can be easily inserted between the outer portion of thebead 36 and the land 26 to pry the closure 10 from the bearing. Due tothe inherent resiliency of the member 34, the bead 36 may be easilysnapped past the land 26 into and out of mounted position without damageto either the closure or to the bearing.

A radially inwardly opening annular groove 50 formed avera es in thebead 36 between a radially inwardly directed lip 52 and the inner Wall45, has spaced side walls generally parallel to the wall 45 and aconical wall 53 formed by the annular portion 42 and located opposite toa transversely rounded rim 54 on the lip 52. An inner annular groove 56in the resilient sealing washer 34 and opening generally radiallyinwardly has uniformly spaced conical side walls between an annular lip58 and the conical por tion 43, the bottom of this groove 56 terminatingwithin or adjacent to the sealing lip 38. The lip 58, which ma, extendlaterally outwardly with respect to the sealing lip 38, preferably hasits outer wall 60 in acommon plane with the outer bead wall 46 andterminates in a transversely rounded rim 61. The sealing washer 34 maybe composed of various rubber-like materials such as a synthetic rubberthat may be easily formed in a mould and vulcanized to the desiredresiliency. This rubber-like material should not :be deleteriouslyaffected by bearing lubricants and should not deteriorate or change itsresiliency in the presence of heat and light. One satisfactoryrubber-like material for my sealing washer 34 comprises aresilientvulcanized synthetic rubber embodying a polymerization product ofbutadiene and acrylic nitrile and/ or a copolymer of butadiene andstyrene.

A dished reinforcing disc 64, which may be stamped out to shape fromresilient sheet metal or formed from plastic or suitable sheet material,has angularly disposed outer and inner rim portions 66 and 67 and anintermediate flat portion 68. The rim portions 66 and 67 respectivelyconform with and demountably fit in the annular seal-ing washer grooves50 and 56 and the intermediate flat portion 68 fits against and conformswith the intermediate wall 40. My rubber-like sealing washer 34 may beeasily and inexpensively produced in a simple moulding and vulcanizingoperation after which, due to its inherent resiliency, it may be easilystretched over and into interfitting relation with the separately formedreinforcing disc 64. The reinforcing disc which snugly fits within thegrooves 50 and '6 laterally urges the resilient sealing lip 38 intosealing position, and since this disc 64 is demountable in the washer34, reinforcing discs of different thicknesses and of differentresiliencies may be interchangeably inserted to provide the desiredlateral stifiness to the washer 34 together with the required yieldablesealing engagement of the sealing lip 38 against the laterally curvedwall of the notch 23. Also, the disc rim 66 preferably bottoms in thewasher groove 50 to compressively urge the periphery of the bead 36 intofirmly resilient sealing engagement with the bottom of the groove 22.

In the embodiment at the left -hand end of Figure 1, a closure,generally indicated at 70 has a moulded washer member 72- composed of asuitable synthetic resilient rubber and provided with an intermediatewall '74 extending between and integral with a peripheral bead '76 and aclosure lip 78 and a conforming dish-shaped reinforcing disc 80 isdemountably received in annular grooves in the bead 76 and in the lip78, all in general accordance with the construction of the closure 10.The resilient bead 76 may be demountably snapped past the land 26 intoand out of firmly seated sealing relation in the left hand groove 22 inthe same manner as described with respect to the sealing member 19. Theclosure lip 78 has a flat inner wall 82 in closely spaced relation tothe annular shoulder 31 and the central bore through this lip 75receives the peripheral wall in closely spaced relation.

I claim:

1. In a closure for demountable positioning across an annular lubricantchamber between a pair of relatively rotatable members one of which hasa groove opening towards the other member, said other member having anannular seal engaging wall, an annular resilient sealing washerperipherally and demountably seated within said groove in sealingengagement with the walls of the groove, a resilient annular lip on theseal in lightly wiping sealing engagement with the seal engaging wall, alaterally resilient reinforcing disc in unit-handling relation with thewasher and laterally urging the washer lip into sealing engagement, andspaced grooved portions on the sealing washer receiving the disc anddemountably and resiliently gripping the reinforcing disc respectivelyat its inner and outer rim portions.

2. In a closure for demountable positioning across an annular lubricantchamber between a pair of relatively rotatable members one of which hasa sealing Washer receiving groove opening generally radially towards theother member, an inherently resilient sealing washer having an annularperipheral bead demountably and sealingly seated in said groove, anannular lip on the washer deformed into lightly Wiping sealingengagement with said other member, the bead and the lip beingrespectively provided with annular grooves opening generally radiallytowards each other, a reinforcing disc in unit-handling relation withthe sealing washer, and the inner and outer disc peripheries beingdemountably gripped by the sealing Washer bead and lip within thesealing washer grooves.

3. In a closure for demountable positioning across an annular lubricantchamber between a pair of relatively rotatable members one of which hasa groove opening towards the other member, an annular resilientlaterally dished sealing washer extending across the lubricant chamber,an annular peripherally extending head on the washer demountably and,deforrnably seated within the groove in sealing engagement with thewalls of the groove, an annular lip in lightly wiping sealing contactagainst said other relatively rotatable member, an intermediate washerwall connecting the lip and the bead, the intermediate washer wall beinglaterally offset from the rear face of the bead and being narrower thansaid bead, a spring-y dished reinforcing disc laterally interfittingwith the sealing washer, and annular grooved portions in the lip and insaid head demountably gripping the reinforcing disc at its inner andouter rims, the sealing washer and reinforcing disc being mountable inand demountable from sealing position as a unit handling assembly.

4. In a closure for demountable positioning across an annular lubricantchamber between a pair of relatively rotatable members one of which hasan annular mounting groove provided with a substantially radial innerwall, the other member having an annular notch, said groove and notchopening generally radially towards each other, an inherently resilientsealing washer extending radially across the lubricant chamber, aperipheral sealing washer bead demountably fitting in the groove andhaving a transversely curved outer face bottoming in said groove andhaving a substantially radialinner wall seated in sea-lingengagementagainst the inner wall of said groove, an annular lip on theWasher in lightly wiping resilient sealing engagement with a wall of theannular notch, a reinforcing disc laterally engaging the sealing washerand extending the major portion of the distance across the lubricantchamber, and annularly groved sealing Washer portions resiliently anddemountably gripping the inner and outer peripheries of the re inforcingdisc.

5. In a closure for demountable positioning across an annular lubricantchamber between a pair of relatively rotatable members one of which hasan annular groove opening towards the other member, said groove having atransversely curved wall extending between an annular land and anannular shoulder, a laterally dished resilient sealing washer extendingacross the lubricant chamber, an annular sealing washer lip in lightlywiping sealing engagement with said other member, a peripheral sealingwasher bead demountably received in said groove, the bead having atransversely curved peripheral wall and a conical face which deformablyand sealingly engages said land, a radial bead face engageable with theannular shoulder, the bead and the sealing washer lip having annulargrooves opening towards each other, and

5 a reinforcing disc laterally interfitting with a'side of theReferences Cited in the file of this patent dished sealing washer, theinner and outer disc periph- UNITED STATES PATENTS eries beingdemountably held by the sealing washer grooves, and the resilient beadbeing compressed be- 2,173,247 Z 1939 tween the disc periphery and saidfirst mentioned mem- 5 gg ag-g -g 5 t k u her and sealmgly seating agamsthe groove wa s on 2,294,105 W angren g 25 1942 Sam member 2,467,049Peterson Apr. 12, 1949

